Exploitation Research Plan: CVE-2026-1310

1. Vulnerability Summary

The Simple calendar for Elementor plugin (versions <= 1.6.6) contains a missing authorization vulnerability in its AJAX handling logic. Specifically, the function miga_ajax_editor_cal_delete is registered to both wp_ajax_miga_editor_cal_delete and wp_ajax_nopriv_miga_editor_cal_delete hooks. This allows unauthenticated users to trigger the deletion of calendar entries. While a nonce check is present, the nonce is exposed to unauthenticated users on pages where the calendar or editor scripts are loaded, and there is no accompanying current_user_can() check to verify the user's permissions.

2. Attack Vector Analysis

• Endpoint: /wp-admin/admin-ajax.php
• Action: miga_editor_cal_delete
• Method: POST
• Parameters:
  • action: miga_editor_cal_delete
  • nonce: A valid WordPress nonce (obtained via frontend script localization).
  • id: The ID of the calendar entry to be deleted (likely a post ID).
• Authentication: Unauthenticated (via wp_ajax_nopriv_ hook).
• Preconditions: The attacker must obtain a valid nonce, which is typically available on any page where the plugin's Elementor widget or shortcode is rendered.

3. Code Flow

1. Hook Registration: The plugin registers the AJAX actions in the main plugin file or an initialization class:

   add_action('wp_ajax_miga_editor_cal_delete', 'miga_ajax_editor_cal_delete');
   add_action('wp_ajax_nopriv_miga_editor_cal_delete', 'miga_ajax_editor_cal_delete');
   

2. Function Execution (miga_ajax_editor_cal_delete):
   • The function is called with the $_POST data.
   • It performs a nonce check: check_ajax_referer('miga_calendar_nonce_action', 'nonce') (Action name inferred).
   • Crucially: It fails to check current_user_can('edit_posts') or similar.
   • It retrieves the entry ID from $_POST['id'].
   • It calls a deletion function, likely wp_delete_post($id, true) or a custom database query via $wpdb.

4. Nonce Acquisition Strategy

The nonce is required for the check_ajax_referer call to pass. In WordPress plugins, these are almost always localized for JavaScript.

1. Identify Script Localization: The plugin likely uses wp_localize_script to pass the nonce to the frontend.
2. Shortcode/Widget: Identify the shortcode or Elementor widget that triggers the script. Based on the plugin name, look for [miga_calendar] or similar (inferred).
3. Extraction Steps:
   • Step 1: Create a public post/page containing the calendar widget.
   • Step 2: Navigate to that page using browser_navigate.
   • Step 3: Use browser_eval to find the nonce in the global JavaScript scope.
   • Target Variable: Likely miga_calendar_params.nonce or miga_ajax_obj.nonce (inferred).
   • Specific JS Check: browser_eval("window.miga_calendar_params?.nonce || window.miga_calendar_vars?.nonce").

5. Exploitation Strategy

1. Target Identification: Determine the ID of a calendar entry (Post ID) to delete.
2. Nonce Extraction: Follow the acquisition strategy above to get a valid nonce for the miga_editor_cal_delete action.
3. Payload Construction:
   • URL: http://[target-ip]/wp-admin/admin-ajax.php
   • Headers: Content-Type: application/x-www-form-urlencoded
   • Body: action=miga_editor_cal_delete&nonce=[NONCE]&id=[TARGET_ID]
4. Execution: Use the http_request tool to send the POST request.
5. Expected Response: A success code (e.g., 1, true, or a JSON success message) and a 200 OK HTTP status.

6. Test Data Setup

1. Create Calendar Entry: Use WP-CLI to create a dummy calendar entry. Assuming the plugin uses a Custom Post Type (CPT) named miga_calendar (inferred):

   wp post create --post_type=miga_calendar --post_title="Target Event" --post_status=publish
   

   Note: Capture the ID returned by this command.
2. Create Trigger Page: Create a page that includes the plugin's frontend component to ensure the nonce is generated and localized:

   wp post create --post_type=page --post_title="Calendar Page" --post_status=publish --post_content='[miga_calendar]'
   

7. Expected Results

• The http_request should return a response indicating the deletion was successful.
• The calendar entry with the specified id should no longer exist in the database.

8. Verification Steps

1. Verify Deletion via WP-CLI:

   wp post exists [TARGET_ID]
   

   If the command returns nothing or an error, the post was successfully deleted.
2. Check Database Directly:

   wp db query "SELECT ID FROM wp_posts WHERE ID=[TARGET_ID]"
   

   An empty result set confirms the deletion.

9. Alternative Approaches

• ID Brute Forcing: Since the vulnerability allows unauthenticated deletion, if the ID of an entry is unknown, an attacker could iterate through recent Post IDs to delete all calendar content.
• REST API Check: Check if the plugin registers a REST API endpoint for the same functionality, as missing authorization often extends across multiple entry points. Look for register_rest_route.
• Action String Guessing: If the nonce action string is not found in the global scope, check the page source for check_ajax_referer calls in the plugin PHP files to identify the exact action name, then look for where that specific action's nonce is localized.